Enhanced poly(3-hydroxybutyrate-co-3-hydroxyvalerate) production from volatile fatty acids by Halomonas sp. YJ01 with 2-methylcitrate cycle.

Volatile fatty acids (VFAs) are suitable substrates for synthesizing poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), wherein propionate is a precursor of PHBV biosynthesis; however, high concentrations are toxic to bacteria. Therefore, VFAs with suitable ratio are needed. Here, with the ratio of acetate: propionate: butyrate being 1:4:2, the maximum PHBV content and the 3HV content were 46.

Magnetic chitosan supported copper particles as a heterogeneous catalyst for benzaldehyde glycol acetal reaction.

In this work, a series of magnetic chitosan (CS) supported-metal catalysts were successfully prepared for the acetalization of benzaldehyde (BzH) with ethylene glycol (EG). The structural properties of the catalysts were characterized by TEM, FT-IR, XRD, XPS, TGA-DTG, SEM-EDX and VSM. The results showed that FeO-CS-Cu(20 %) catalyst possessed the best catalytic efficiency in all prepared catalysts due to its suitable acidity and excellent stability when they were utilized in the acetalization reaction to generate benzaldehyde glycol acetal.

A review of tungsten trioxide (WO)-based materials for antibiotics removal via photocatalysis.

Antibiotics are extensively used in human medicine and animal breeding. The use of antibiotics has posed significant risks and challenges to the natural water environment. On a global scale, antibiotics have been frequently detected in the environment, azithromycin (254-529 ng·L), ciprofloxacin (245-1149 ng·L), ofloxacin (518-1998 ng·L), sulfamethoxazole (1325-5053 ng·L), and tetracycline (31.

Transition Metal-Promoted Carbon-Silicon Solid Acid Catalysts for the Synthesis and Process Optimization of Benzaldehyde Glycol Acetal.

A series of transition metal (M)-promoted carbon-silicon (C-M-Si; M=Mn, Fe, Co, Ni, Cu, Zn, Zr) solid acid catalysts with designated molar ratio of M/Si=1 : 8 were fabricated and exploited for acetalization of benzaldehyde (BzH) with ethylene glycol (EG). The physical and chemical properties of these C-M-Si catalysts prepared by sol-gel method were characterized by various techniques, namely, SEM, EDS, TGA-DTG, BET, XRD, FTIR, XPS, and NH -TPD. Among various examined acidic C-M-Si catalysts, the C-Fe-Si catalyst exhibited the optimal catalytic activity with the benzaldehyde glycol acetal (BEGA) yield of 97.

Temporal dynamics of SARS-CoV-2 genome mutations that occurred on an aircraft.

We analyzed variations in the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome during a flight-related cluster outbreak of coronavirus disease 2019 (COVID-19) in Shenzhen, China, to explore the characteristics of SARS-CoV-2 transmission and intra-host single nucleotide variations (iSNVs) in a confined space. Thirty-three patients with COVID-19 were sampled, and 14 were resampled 3-31 days later. All 47 nasopharyngeal swabs were deep-sequenced.

Non-thermal plasma-enhanced catalytic activation of Mn-Zr-La/AlO catalyst for meta-xylene degradation: Synergetic effects and degradation mechanism.

The LaMnO catalysts doped with transition metal (Zr, Co, Fe) were prepared. The influencing factors (the catalyst type, the initial concentration, the gas flow, and oxygen content) on the degradation efficiency by the non-thermal plasma synergistic the LaMnO catalysts doped with Zr, Co and Fe were investigated systematically. The degradation mechanism of the meta-xylene degradation by the non-thermal plasma synergistic Mn-Zr-La/AlO was researched.

Possible recombination between two variants of concern in a COVID-19 patient.

We identified an individual who was coinfected with two SARS-CoV-2 variants of concern, the Beta and Delta variants. The ratio of the relative abundance between the two variants was maintained at 1:9 (Beta:Delta) in 14 days. Furthermore, possible evidence of recombinations in the and genes was found.

The Disease Severity and Clinical Outcomes of the SARS-CoV-2 Variants of Concern.

With the continuation of the pandemic, many severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have appeared around the world. Owing to a possible risk of increasing the transmissibility of the virus, severity of the infected individuals, and the ability to escape the antibody produced by the vaccines, the four SARS-CoV-2 variants of Alpha (B.1.

A SARS-CoV-2 Delta variant outbreak on airplane: vaccinated air passengers are more protected than unvaccinated.

In-fight transmission of SARS-CoV-2 Delta variant could occur on airplane, and close contact is the main mode of transmission. Vaccination still protects against the Delta variant transmission.

Visualization of the interaction of water aerosol and nanofiber mesh.

Face masks play a critical role in reducing the transmission risk of COVID-19 and other respiratory diseases. Masks made with nanofibers have drawn increasingly more attention because of their higher filtration efficiency, better comfort, and lower pressure drop. However, the interactions and consequences of the nanofibers and microwater droplets remain unclear.

A data driven agent-based model that recommends non-pharmaceutical interventions to suppress Coronavirus disease 2019 resurgence in megacities.

Before herd immunity against Coronavirus disease 2019 (COVID-19) is achieved by mass vaccination, science-based guidelines for non-pharmaceutical interventions are urgently needed to reopen megacities. This study integrated massive mobile phone tracking records, census data and building characteristics into a spatially explicit agent-based model to simulate COVID-19 spread among 11.2 million individuals living in Shenzhen City, China.

Using Proper Mean Generation Intervals in Modeling of COVID-19.

In susceptible-exposed-infectious-recovered (SEIR) epidemic models, with the exponentially distributed duration of exposed/infectious statuses, the mean generation interval (GI, time lag between infections of a primary case and its secondary case) equals the mean latent period (LP) plus the mean infectious period (IP). It was widely reported that the GI for COVID-19 is as short as 5 days. However, many works in top journals used longer LP or IP with the sum (i.

COVID-19-Related Stressors and Mental Health Among Chinese College Students: A Moderated Mediation Model.

This study aims to examine the relation between COVID-19-related stressors and mental health among Chinese college students during the pandemic outbreaks, and the possible mediator or moderator between them. Five hundred and fifty Chinese college students were invited to complete an anonymous survey, and the data were analyzed with SPSS 16.0 software.

Reinfection or Reactivation of Severe Acute Respiratory Syndrome Coronavirus 2: A Systematic Review.

As the pandemic continues, individuals with re-detectable positive (RP) SARS-CoV-2 viral RNA among recovered COVID-19 patients have raised public health concerns. It is imperative to investigate whether the cases with re-detectable positive (RP) SARS-CoV-2 might cause severe infection to the vulnerable population. In this work, we conducted a systematic review of recent literature to investigate reactivation and reinfection among the discharged COVID-19 patients that are found positive again.

A newly identified linear epitope on non-RBD region of SARS-CoV-2 spike protein improves the serological detection rate of COVID-19 patients.

Background: Serological test is helpful in confirming and tracking infectious diseases in large population with the advantage of fast and convenience. Using the specific epitope peptides identified from the whole antigen as the detection antigen is sensitive and relatively economical. The development of epitope peptide-based detection kits for COVID-19 patients requires comprehensive information about epitope peptides.

COVID-19-Related Stressors and Chinese Adolescents' Adjustment: The Moderating Role of Coping and Online Learning Satisfaction.

The present study aims to examine the main and interactive relations of COVID-19-related stressors, coping, and online learning satisfaction with Chinese adolescents' adjustment during the COVID-19 pandemic. A total of 850 adolescents from three Chinese secondary schools participated in the survey during the pandemic outbreak, and the data were analyzed by hierarchical linear regression. The results show that COVID-19-related stressors were a vulnerability factor in predicting adjustment.

Family exposure and the impact of containment measures to children with coronavirus disease 2019 outside Hubei, China: a cross-sectional study.

Background: In response to the ongoing epidemic of coronavirus disease 2019 (COVID-19), China has carried out restrictive disease containment measures across the country.

Methods: In this cross-sectional study, we collected demographic and epidemiological data of 376 laboratory-confirmed cases of COVID-19 among children younger than 18 years of age. Using descriptive statistics and odds ratios, we described the odds of exposure outside the family after the implementation of control measures compared to before.

Viral RNA level, serum antibody responses, and transmission risk in recovered COVID-19 patients with recurrent positive SARS-CoV-2 RNA test results: a population-based observational cohort study.

Managing recovered COVID-19 patients with recurrent-positive SARS-CoV-2 RNA test results is challenging. We performed a population-based observational study to characterize the viral RNA level and serum antibody responses in recurrent-positive patients and evaluate their viral transmission risk. Of 479 recovered COVID-19 patients, 93 (19%) recurrent-positive patients were identified, characterized by younger age, with a median discharge-to-recurrent-positive length of 8 days.

Modelling the Measles Outbreak at Hong Kong International Airport in 2019: A Data-Driven Analysis on the Effects of Timely Reporting and Public Awareness.

Background: Measles, a highly contagious disease, still poses a huge burden worldwide. Lately, a trend of resurgence threatened the developed countries. A measles outbreak occurred in the Hong Kong International Airport (HKIA) between March and April 2019, which infected 29 airport staff.

Epidemiology and transmission of COVID-19 in 391 cases and 1286 of their close contacts in Shenzhen, China: a retrospective cohort study.

Background: Rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Wuhan, China, prompted heightened surveillance in Shenzhen, China. The resulting data provide a rare opportunity to measure key metrics of disease course, transmission, and the impact of control measures.

Methods: From Jan 14 to Feb 12, 2020, the Shenzhen Center for Disease Control and Prevention identified 391 SARS-CoV-2 cases and 1286 close contacts.

Highly efficient decomposition of toluene using a high-temperature plasma-catalysis reactor.

Plasma-catalysis technologies (PCTs) have the potential to control the emissions of volatile organic compounds, although their low-energy efficiency is a bottleneck for their practical applications. A plasma-catalyst reactor filled with a CeO/γ-AlO catalyst was developed to decompose toluene with a high-energy efficiency enhanced by the elevating reaction temperature. When the reaction temperature was raised from 50 °C to 250 °C, toluene conversion dramatically increased from 45.

U13 → C13 mutation in the variable region of the NA gene 3'UTR of H9N2 influenza virus influences the replication and transcription of NA and enhances virus infectivity.

The untranslated regions within viral segments are the essential promoter elements required for the initiation of viral replication and transcription. The end of the UTR sequence and part of the ORF sequence constitute the packaging signal for progeny viruses. To explore the influence of single-point and multi-site joint mutations in the UTR of the NA gene on the viral expression, we select clones with upregulated expression of the reporter gene and analyze their sequence characteristics.

Mechanism of CO-formation promotion by Au in plasma-catalytic oxidation of CH over Au/γ-AlO at room temperature.

The plasma-catalytic oxidation of methane (CH) is a potential reaction for controlling CH emissions at low temperatures. However, the mechanism of the CH plasma-catalytic oxidation is still unknown, which inhibits the further optimization of the oxidation process. Herein, a CH oxidation mechanism over an Au/γ-AlO catalyst was proposed based on our experimental findings.